FIX the lockscreen auto-unlocking for lockscreen-launched activities.

Revert "Don't start keyguard in an attempt to exit it."

This reverts commit c996bc4a2fedb3680587dda5e9c8da93e51f03f8.

Change-Id: I4bf70d2dd99b4c89e0c7d8e2130004a95358dd66